Answer: percentage
Explanation: A logarithmic price scale uses the percentage of change to plot data points, so, the scales values are not positioned at equal distances. To visualize growth rates, real GDP per capita is plotted in natural logs. By plotting on a logarithmic scale, one can see the percent increases, rather than the absolute increases. Using logarithms means that every step up the y-axis is an identical percent change in real GDP per capita. Logarithm scale helps to respond accurately to skewness towards large values while showing percent changes or multiplicative factors.